Rotary thermal engine

ABSTRACT

Thermal rotating engine in a closed circuit using chambers having a variable volume limited by two successive blades of a flash wheel, two lateral rims connected to the blades and a portion of liquid ring comprised between these two blades. The drive fluid drawn off from each chamber when the latter takes up the minimum volume, is injected again into the chamber after having been heated up in a hot source. Application to all cases where a certain power in a small volume proves to be necessary. It is suitable particularly for automatic use, due to its slight pollution.

I United States Patent [111 3,905,198 Malaval Sept. 16, 1975 ROTARYTHERMAL ENGINE [76] Inventor: Claude Malaval, 39 rue des f E'fanm1erMartm schwadmn coquelicotg 92160 Antony France ASSZSILIH! bxammerl-l. Burks, Sr

Alrorney, Agent, or FirmSughrue, Rothwell, Mlon, [22] Filed: Oct. 17,1973 Zinn & Macpeak 2] A l. N .1 407,129 I 1 pp 57 ABSTRACT D Thermalrotating engine in a closed circuit using [30] Forelg Apphcamm PnontyDam chambers having a variable volume limited by two L 1972 France72-37041 successive blades of a flash wheel, two lateral rims connectedto the blades and a portion of liquid ring [52] US. Cl. 60/669 omprisedbetween these two blades, [5|] Int. Cl. v. FOlk 11/00 The drive fluiddrawn Off from each Chamber whfin [58] F'eld Search 1 the latter takesup the minimum volume, is injected again into the chamber after havingbeen heated up in h t [56] References Cited a ooijlrce l i UNITED STATESPATENTS Appllcatlon to al cases where a certain power m a small volumeproves to be necessary. It is suitable Q9944 9/1922 Nash 60/108 Rparticularly for automatic use, due to its slight 3.l90,072 6/l965Berryer. 60/l08 R ouution 3,495,402 2 1970 Yates l l v v 60/36 p 3.589126 6/1971 Zotto 60/36 7 Claims, 3 Drawing Figures PATENTEG sE 1 6 ms 1,9 if} 1 $19 ROTARY THERMAL ENGINE BACKGROUND OF THE INVENTION 1. Fieldof the Invention The present invention concerns a rotary thermal en ginedrawing away a drive fluid, in a closed circuit according to a cyclealmost similar to the Stirling cycle.

2. Description of the Prior Art In engines implementing the Stirlingcycle or an almost similar cycle, as present known, drive gases aremoved from a hot chamber to a cold chamber by means of the alternatinglenear movement of a piston in a cylinder. Expansion is effected in aspace comprised between the said piston and another piston placed belowthe first.

Such a device requires elements for transforming the rectilinearmovement of the piston into a rotating movement of the drive shaftleading to an appreciable increase in the weight and the price of thedevice. Moreover, such an engine implements piston rings operating athigh temperature whose reliabiliy is still sometimes haphazard.

It is evidently possible to avoid using chambers having variable volumelimited by at least a piston, by using chambers having flexible wallsbut then, the metal constituting the wall of the chamber would besubmitted to particularly severe temperature and fatigue conditions andthe problem of transforming the rectilinear movement into a rotatingmovement remains unsolved.

The inventor has preferred to use the principle of the rotating engine,thus avoiding, moreover, the use of in termediate elements fortransforming the rectilinear movement into a circular movement. It isindeed a known practice to use a stator having a definite geometricalshape, within which a rotor limiting, with the stator, during itsrotation, chambers having a variable volume, is made to rotate but allthe sealing and cooling problems set by devices of that type are alsoknown. The inventor has overcome these various difficulties byimplementing chambers one of whose walls is constituted by a portion ofliquid ring obtained by driving in a rotating movement the liquidcontained in a cylindrical body having a horizontal axis by means of aflash wheel also having a horizontal axis but excentric in re' lation tothe axis of the cylindrical body in the same way as a compressor or pumpof the liquid ring type. In such a structure, the chamber is limited bytwo blades, by the portion of liquid ring which they determine and bytwo lateral rims perpendicular to the blades. The chamber is all thesmaller as the two blades which limit it on two sides are immerseddeeper in the liquid ring. The variation of the volume of the chamber istherefore effected without any seal or friction other than that of theliquid ring driven by the rotation of the blades and remaining veryslight. The inventor has constituted a rotating thermal engine bycombining a certain number of such cylindrical bodies in which a fluidflows in a closed circuit. That fluid is at least partly put intocontact with a hot source and a cold source according to the cyclealmost similar to the Stirliing cycle.

The object of the invention is a rotating thermal en gine constituted bya hot source, a cold source, a cylindrical volume, several flash wheelsfltted with lateral rims and a certain quantity ofliquid, the axis ofthe said flash wheels being parallel and excentric in relation to theaxis of the cylindrical volume, the rotation of each flash wheel givingrise to a liquid ring, limiting, with the rims of the said wheel, acylindrical body which the successive blades divide up into chambershaving a vari able volume, characterised in that a drive fluid moves ina closed circuit comprising the hot source and the cold source arrangedoutside the cylindrical bodies.

It is known that at the present time, rotating internal combustionengines have the disadvantage of produc ing particularly polluting gaseswhen they operate at low speed. In known rotating engines, it is notpossible to draw off or inject gases from the vicinity of the centre ofthe device because of the high temperature of the rotor and of thedifficulty in constituting rotating seals impervious to thesetemperatures so that communications of the chamber with the outside canbe made only by the stator, this preventing the drawing off of gasesduring a cycle to re-inject them after a heat treatment at the mostfavourable point for obtaining a homogenous mixture. On the contrary, inthe device according to the invention, the chamber itself rotates on theaxis and only the wall formed by the portion of liquid ring movesforward or backward in a radial direction it is therefore easy to choosethe place at which the injection is to be made. The very structure ofthe engine then allows the drive fluid to be brought close to the heatsource and to re-inject it in the best output conditions, whatever thespeed of rotation of the engine may be and to avoid causing acorrelation between the rotation speed of the engine and the combustionrate of the heating gases of the hot source.

The object of the invention is therefore also a rotat ing thermal engineof the closed circuit type, constituted according to the precedingdescription, characterised in that communication means enable at least apart of the gases to be drawn off successively from each chamber at theinstant when the latter takes up the minimum volume to re-inject them ina chamber having an increasing volume after having put them in contactwith the hot source.

In a device according to the invention, due to appro priate means, thedrive fluid is therefore drawn off successively from the chambers at aninstant when these latter take up the minimum volume to lead it into anexchanger device forming the hot source where the drive fluid is heatedthen sent back into a chamber whose volume is increasing so that thishot fluid provides drive force during its expansion.

An engine according to the invention operates between a hot source withwhich the drive fluid drawn off from the chamber taking up the minimumvolume is put in contact and a cold source with which the cold fluiddrawn off during compression is put in contact to re-inject it into thechamber taking up the maximum volume.

The object of the invention is therefore also a thermal engineconstituted according to the preceding descriptions. characterised inthat means enable a part of the drive fluid in the chambers in thecompression phase to be drawn off, the said fluid to be put in contactwith the said cold source and sent back into the following chambers atthe instant when the compression is the lowest.

It should be observed that the liquid ring does not heat up permanentlyand does not have a tendency to become vaporized as circumstances maylead it to be believed. Indeed, the direct contact with the hot gasestakes place only during a short fraction of the revolution cycle,moreover by means of the smallest surface,

whereas during all the remainder of the revolution cycle, the surface incontact with the gas is greater and the liquid ring remains permanentlyin contact with the wall of the cylindrical body, itself cooled by awater circulation or by cooling fins.

Lastly, it should be observed that the portion of ring comprised in thechamber where the maximum cmpression takes place is subjected to apressure greater than that to which the portion of ring limiting thechamber in which the expansion takes place the result of this is a forcewhich tends to make the liquid ring rotate in the direction of rotationof the blades and de creases the drive force of the rotating liquid aswell as the corresponding friction.

The invention is described in greater detail in the example herebelow,having no limiting character, with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view,partially in section, showing diagrammatically the central part of theengine of the present invention FIG. 2 is a diagrammatic cutaway viewshowing the connecting of the central part of the engine of FIG. 1 tothe two sources. FIG. 3 is a sectional view of the engine of FIGS. 1 and2 showing the feeding of the chambers with drive fluid.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows diagrammaticallythe central part of an engine implementing a variant of the inventionwhich comprises two cylindrical bodies having four chambers arranged ina line on the same shaft, arranged in the same cylindrical volume I. InFIG. I, a cylindrical volume through which a shaft 2 passes may bedistinguished at l. The cylindrical volume is therefore constituted bytwo coaxial cylindrical bodies 3 and 4 having the same diameter.

The cylindrical body 3 is limited by the sides 5 and 6. The cylindricalbody 4 is limited by the sides 7 and 8. Each of the sides supportsrespectively the bearings 9, l0 and I] of shaft 2. The sides 5 and 7made fast with each other by the bearing 10 constitute a volumecontaining ducts and the hub of which descriptions are given further on.

Within the cylindrical body 3, the existence of the blade 12constituting a wall common to two contiguous chambers and in thecylindrical body 4, the existence of the blade 13 fulfilling, in thebody 4, the same function as the blade 12, will be observed. At itslateral ends, the blade I2 bears rims l4 and I5 and the blade 13 bearsthe rims l6 and 17. Flexible elements I8 and 19 put the rims l5 and 16of the blades 12 and 13 in contact respectively with the sides 5 and 7.

A pipe 2] enabling the drive fluid to be drawn off at the instant whenthe chamber reaches the minimum volume is arranged between the sides 5and 7. A pipe 22 enables the fluid to be re-injected after its pass atthe hot source (not shown in this figure).

Likewise, a pipe 23 enabling a part of the fluid to be drawn off towardsthe cold source (not shown in that 25 and to the cold source 25'. Twopipes 21 and 22 making the chambers communicate with the hot source 25by means of the tubes 27 and 28 extending, respectively, the pipes 21and 22, are arranged between the sides 5 and 7. In the hot source 25,the tubes 27 and 28 are welded along two generating lines to tubes 40greatly flattened and wound in a spiral. Each flat tube 40 is reinforcedby oblique steel wires 40' arranged in a regular pitch. These wires arefixed to the flat tubes 40.

The spiral of the flat tubes such as 40 ends at the centre of the hotsource in a central tubing 29 whence other flat tubes such as 40 woundin the reverse direction leave. The burner 31 is arranged at one end ofthe central tubing 29. The liquid fuel is sent by the sprayer 32 towardsa heating grill 33 constituted by a metallic strip 66 insulated byceramic elements 67. That spiral coil is heated when the engine isstarted up by Joule effect by means of a storage cell battery (notshown). When the spiral winding has reached operating temperature, thespiral winding vapourizes the fuel. The air sucked in by the nozzle 34,flowing between the collar 30 and the casing 26 is heated and burns withthe fuel. The combustion gases escape through the tubing 35 after havingheated the drive fluid flowing in the flat tubes 27 and 28.

The device acting as a heat source enables the use of very thin tubes 27and 28 making thermal exchanges with the hot source easier. Indeed, thepressures brought into play are retransmitted by means of the steelwires up to the outside collar 30 made of a metal which is sufficientlythick to bear the whole of the pressure obtained in the tubing by meansof the hot source.

The cold source 25', constituted in the same way as the hot source 25,is fed with cooling fluid. The pipes 23 and 24 widen out respectivelyinto the tubes 37 and 38 to form, subsequently, flat spiral tubes as inthe hot source. They are connected up by the central duct 36.

To enable the slowing down of the rotating speed of the thermal engine,a by-pass valve 41 whose shutter 41' is linked with the adjusting of thecombustion discharge is arranged between the tubes 21 and 22. Thatarrangement enables the hot source 25 to be maintained at a hightemperature when the burner and the engine operate at low speed andcancels, simultaneously. the effects of thermal inertia.

Lastly, FIG. 2 makes it possible to understand the principle of thefeeding of the chambers by the hot source 25 and the cold source 25'.

The lateral rim 15 does not bear with all its surface against theleft-hand face of the side 5. A certain gap appears on the periphericalpart although the spring 18 may tend to press the blade wheel againstthe wall 7. Indeed, the wall 5 has, at its central part, a hub 20drilled at certain places with circular ports 6]. Each of the circularports such as 61 is in relation with one of the pipes such as 21, 22, 23or 24 (FIG. 1 or 2). When a port such as 71 of the lateral rim comesopposite a port of a boss such as 61, a communication between the sourceand the chamber of the engine is established. At the instant in questionin FIG. 2, a port such as 72 in the rim 16 does not establish anycontact with a source.

FIG. 3 shows a cross-section of the engine; a profile of one of theblades [2 driving the liquid contained in the cylindrical body limitedby a circle 4 shown in dotted lines may be seen therein. The liquidforms. in its turn, a cylindrical wall whose inside face is limited bythe dotted line 45. The blades 12, 46, 47 and 48 limit, with the wall ofthe liquid ring 45, four chambers 51, 52, 53 and 54, the two lateralfaces of these chambers being limited by rims such as 14 and 15 (HO. 1or FIG. 2).

Circular ports formed in the boss 20, connected up respectively to thepipes 21 and 22 feeding the hot source have been shown at 61 and 62.Ports formed in the boss 20, connected up respectively to the pipes 23and 24 have been shown at 63 and 64.

Lastly, the circular port 72 drilled in the lateral rim is seen in thechamber 52. One such feed port exists per chamber, the chamber 53 beingprovided with the opening 73.

in actual fact, four circular ports are drilled in the boss 20, inconstant communication with one of the four feed pipes of the twosources. Likewise, four circular ports are drilled in the lateral rimsin contact with the central sides 5 and 7, each port in turn putting thechamber to which it corresponds in communication, during a short period,with the hot gas inlet, the cold gas outlet, the cold gas inlet, the hotgas outlet.

The result of this is that in the case of the figure where the number ofchambers having variable volumes per cylindrical body is four, the drivefluid is drawn off by the port 61 in the chamber during the quarter of acycle corresponding to the minimum vol ume (chamber 51 and pointedtowards the hot source at the following quarter of a cyclecorresponding, in FIG. 3, to the chamber 52, the fluid coming from thehot source is injected by the port 62. The hot gas then expands,providing a drive force.

At a following quarter ofa cycle, the chamber having a variable volumereceives, by the port 63, a certain quantity of fluid cooled by the coldsource 25'. During the last quarter of a cycle, a part of the fluid isdrawn off by the port 64 in the chamber having a variable volume ispointed towards the cold source by the pipe 23.

The fluid supplies, in each chamber having a variable volume, a driveforce during the whole of the expansion of the fluid, that is, from thepressing of the port of the chamber in front of the fixed port 62 untilit passes in front of the fixed port 63. During the expansion, thepressure in the chamber is higher than in the chamber which preceeds itthe result of this is an action on the wall of the liquid ring whichtends to move the latter in the rotating direction of the engine. A partof the energy thus supplied is recuperated by means of fins such as 12'(FIG. 3) or 46' (FIGS. land 3) which produce a drive of the wheel in thedirection of its rotation.

The device according to the invention has been described hereinabovewith two cylindrical bodies installed on the same shaft. It isself-evident that it is also possible to install only one or more thantwo, for example, four, six or eight, without going beyond the scope ofthe invention. Likewise, bodies comprising four blades limiting fourchambers have been described. The inventor has also made experiments oncylindrical bodies containing six and eight chambers, which could be agreater advantage if it is required to drive a device having low inertiawhich must nevertheless be actuated with a very regular movement.Applications for such an engine are particularly numerous. This enginegives high power for a low volume moreover, it adapts itself very wellto a variable speed rate. It is recommended more particularly fortraction, more particularly on automobiles, tractors, dinghies, etc. Asa fixed unit, it may be combined with an alternator or a compressor.Moreover, that engine has the advantage of using the most diverse liquidor gaseous fuels.

I claim: 1. A cylindrical rotating thermal engine comprising: acylindrical casing, a quantity of liquid within said casing, a source ofheat exterior of said cylindrical casing, a source of cold exterior ofsaid cylindrical casing, a plurality of wheels inside said casingmounted for rotation therein, each of said wheels bearing radial vanesfitted with lateral rims, the axis of said wheels being parallel andeccentric in relation to the axis of the cylindrical casing,

a cylindrical ring of said liquid formed by rotation of each wheel, thelateral rims and the successive vanes of said wheels defining successivechambers having variable volume,

a propellant contained in said successive chambers,

and

means for displacing said propellant in a closed circuit along a pathincluding said chambers for Sue cessive compression, placement incontact with a source of heat, expansion to provide power, partialexhaustion from one of said chambers submitted to compression, andplacement into contact with the cold source before rejection into thechamber tak' ing up the maximum volume.

2. The rotating thermal engine according to claim 1, wherein saidpropellant directing means includes first means communicating saidchambers with the source of heat during a predetermined interval oftime.

3. The rotating thermal engine according to claim 2, wherein saidpropellant directing means includes a second communication means forplacing a fraction of the propellant in communication with the coldsource during a predetermined time interval.

4. The rotating thermal engine of the closed circuit type according toclaim 2, wherein the heat source communicating means includes means fordrawing off at least a part of the gases from each chamber at the instant when the latter takes up minimum volume and putting said gasesinto contact with the source of heat and reinjecting them into a chamberwhose volume is increasing.

5. The rotating thermal engine of the closed circuit type according toclaim 3, wherein said second communication means includes means fordrawing off a part of the gases from the chambers having a variablevolume during compression and putting them into contact with said coldsource and means for reinjecting said gases into a chamber whose volumeat that moment is maximum.

6. The rotating thermal engine of the closed circuit type according toclaim 2, in which the propellent directing means enabling a part of thegas system to be drawn off from or injected into chambers having avariable volume, comprises: a hub, four bores formed in the casing sidesin the vicinity of the hub, heat exchangers external to the casingforming said hot and cold sources and ducts communicating the heatexchangers with said bores, and wherein a lateral rim of each chamber isprovided in the vicinity of the hub with a circular portioncommunicating said chambers with said heat exchangers when the circularport comes in alignment with a corresponding bore formed within the sideof the cylindrical casing.

7. The rotating thermal engine of the closed circuit type, according toclaim 1, wherein the communication means between each chamber and thesource of heat is provided with a bypass valve.

1. A cylindrical rotating thermal engine comprising: a cylindricalcasing, a quantity of liquid within said casing, a source of heatexterior of said cylindrical casing, a source of cold exterior of saidcylindrical casing, a plurality of wheels inside said casing mounted forrotation therein, each of said wheels bearing radial vanes fitted withlateral rims, the axis of said wheels being parallel and eccentric inrelation to the axis of the cylindrical casing, a cylindrical ring ofsaid liquid formed by rotation of each wheel, the lateral rims and thesuccessive vanes of said wheels defining successive chambers havingvariable volume, a propellant contained in said successive chambers, andmeans for displacing said propellant in a closed circuit along a pathincluding said chambers for successive compression, placement in contactwith a source of heat, expansion to provide power, partial exhaustionfrom one of said chambers submitted to compression, and placement intocontact with the cold source before rejection into the chamber taking upthe maximum volume.
 2. The rotating thermal engine according to claim 1,wherein said propellant directing means includes first meanscommunicating said chambers with the source of heat during apredetermined interval of time.
 3. The rotating thermal engine accordingto claim 2, wheRein said propellant directing means includes a secondcommunication means for placing a fraction of the propellant incommunication with the cold source during a predetermined time interval.4. The rotating thermal engine of the closed circuit type according toclaim 2, wherein the heat source communicating means includes means fordrawing off at least a part of the gases from each chamber at theinstant when the latter takes up minimum volume and putting said gasesinto contact with the source of heat and reinjecting them into a chamberwhose volume is increasing.
 5. The rotating thermal engine of the closedcircuit type according to claim 3, wherein said second communicationmeans includes means for drawing off a part of the gases from thechambers having a variable volume during compression and putting theminto contact with said cold source and means for reinjecting said gasesinto a chamber whose volume at that moment is maximum.
 6. The rotatingthermal engine of the closed circuit type according to claim 2, in whichthe propellent directing means enabling a part of the gas system to bedrawn off from or injected into chambers having a variable volume,comprises: a hub, four bores formed in the casing sides in the vicinityof the hub, heat exchangers external to the casing forming said hot andcold sources and ducts communicating the heat exchangers with saidbores, and wherein a lateral rim of each chamber is provided in thevicinity of the hub with a circular portion communicating said chamberswith said heat exchangers when the circular port comes in alignment witha corresponding bore formed within the side of the cylindrical casing.7. The rotating thermal engine of the closed circuit type, according toclaim 1, wherein the communication means between each chamber and thesource of heat is provided with a bypass valve.